Display panel, method for fabricating the same, and display device

ABSTRACT

This disclosure relates to the field of display technologies, and discloses a display substrate, a method for fabricating the same, and a display device. The display substrate includes: a substrate, and a plurality of pixels and a pixel definition layer on the substrate, wherein the pixels include long sides and short sides; and the pixel definition layer includes long-side sections adjacent to the long sides, and short-side sections adjacent to the short sides, wherein heights of the long-side sections are greater than heights of the short-side sections.

This application is a National Stage of International Application No.PCT/CN2018/102562, filed Aug. 27, 2018, which claims the priority ofChinese Patent Application No. 201711147209.0, filed with the ChinesePatent Office on Nov. 17, 2017, and entitled “A display panel, a methodfor fabricating the same, and a display device”, both of which arehereby incorporated by reference in their entireties.

FIELD

The present disclosure relates to the field of display technologies, andparticularly to a display panel, a method for fabricating the same, anda display device.

BACKGROUND

An Organic Light-Emitting Diode (OLED) display device has been acceptedas a very promising next-generation display technology due to a smallthickness, a low weight, a wide angle of view, active light-emission,consecutive adjustability of emitted light color, a low cost, a highresponse speed, lower power consumption, low driving voltage, a wideoperating temperature range, a simple production process, high lightemission efficiency, a flexible display, and other advantages.

SUMMARY

At least one embodiment of this disclosure provide a display substrateincluding: a substrate, and a plurality of pixels and a pixel definitionlayer on the substrate, wherein:

the plurality of pixels include long sides and short sides; and

the pixel definition layer includes long-side sections adjacent to thelong sides, and short-side sections adjacent to the short sides, whereinheights of the long-side sections are greater than heights of theshort-side sections.

For example, a length l1 of at least one of the long sides, a length l2of at least one of the short sides, a height h1 of at least one of thelong-side sections, and a height h2 of at least one of the short-sidesections satisfy h1/h2=(⅓˜¾)l1/l2.

For example, a height h1 of at least one of the long-side sectionsranges from 1 μm to 5 μm, and a height h2 of at least one of theshort-side sections ranges from 0.5 μm to 2.5 μm.

For example, wall sides of the pixel definition layer facing theplurality of pixels are slope faces.

For example, each of the slope faces is at a slope angle to thesubstrate; a slope angle of the slope faces facing the long sides of theplurality of pixels is equal to a slope angle of the slope faces facingthe short sides of the plurality of pixels.

For example, the pixel definition layer includes a lyophilic materiallayer, and a lyophobic material layer located on a side of the lyophilicmaterial layer away from the substrate.

For example, a thickness s1 of the lyophobic material layer, and athickness s2 of the lyophilic material layer of a long-side sectionsatisfy s1≥½*s2.

At least one embodiment of this disclosure further provides a displaydevice including the display substrate above.

At least one embodiment of this disclosure further provides a method forfabricating a display substrate, the method including a step of:

forming a pixel definition layer on a substrate, wherein the pixeldefinition layer includes long-side sections adjacent to long sides of aplurality of pixels, and short-side sections adjacent to short sides ofthe plurality of pixels, and heights of the long-side sections aregreater than the heights of short-side sections.

For example, forming the pixel definition layer on the substrateincludes:

forming a thin film of the pixel definition layer on the substrate;

forming a plurality of opening areas on the thin film of the pluralityof pixel definition layer, wherein each of the opening areas correspondsto one of the plurality of pixels; and

thinning sections of the thin film of the pixel definition layer, whichare adjacent to the shot sides of the pixels.

For example, forming the pixel definition layer on the substrateincludes:

forming a thin film of the pixel definition layer on the substrate;

thinning sections of the thin film of the pixel definition layer, whichare adjacent to the shot sides of the plurality of pixels; and

forming a plurality of opening areas on the thin film of the pixeldefinition layer, wherein each of the opening areas corresponds to oneof the plurality of pixels.

For example, forming the thin film of the pixel definition layer on thesubstrate includes:

forming a lyophilic material layer on the substrate; and

forming a lyophobic material layer on a side of the lyophilic materiallayer away from the substrate.

For example, the method further includes a step of: forming an organiclight-emitting layer in the opening areas using solution.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic structural diagram of a display substrateaccording to an embodiment of this disclosure.

FIG. 2 is a schematic diagram of FIG. 1 in a sectional view along A-Aaccording to the embodiment of this disclosure.

FIG. 3 is a schematic diagram of FIG. 1 in a sectional view along B-Baccording to the embodiment of this disclosure.

FIG. 4 is a schematic diagram of FIG. 1 in a sectional view along C-Caccording to the embodiment of this disclosure.

FIG. 5 is a schematic structural diagram of a display device accordingto an embodiment of this disclosure.

FIG. 6 is a schematic flow chart of a method for fabricating a displaysubstrate according to an embodiment of this disclosure.

FIG. 7 is a schematic flow chart of a method for fabricating a displaysubstrate according to another embodiment of this disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

In order to improve the uniformity of the thickness of a film throughink-jet printing in a display substrate so as to improve the displayeffect of the display device, and to prolong the service lifetimethereof, embodiments of this disclosure provide a display substrate, amethod for fabricating the same, and a display device. In order to makethe object, the technical solutions, and the advantages of thisdisclosure more apparent, this disclosure will be described below infurther details with reference to the embodiments thereof.

As illustrated in FIG. 1, a display substrate according to an embodimentof the disclosure includes a substrate 1, and a plurality of pixels 7and a pixel definition layer 8 located on the substrate 1, where:

the pixels 7 include long sides 6 and short sides 5; and

the pixel definition layer 8 includes long-side sections 2 adjacent tothe long sides 6, and short-side sections 3 adjacent to the short sides5, where the heights of the long-side sections 2 are greater than theheights of the short-side sections 3.

The particular type of the display substrate will not be limited, andfor example, can be an OLED display substrate or a quantum dot displaysubstrate. The OLED display substrate will be described in this contextby way of an example. Since the OLED display substrate includes thepixel definition layer located on the substrate, and the pixels formedin pixel opening areas defined by the pixel definition layer (i.e.,areas defined by the long-side sections and the short-side sections ofthe pixel definition layer), the long-side sections and the short-sidesections of the pixel definition layer correspond respectively to thelong sides and the short sides of the corresponding pixels.

In a film formation process of the OLED display substrate, a solutionprocess, e.g., the ink jet printing technology, the screen printingtechnology, etc., has been accepted as an important technology oflarge-size and massive printing due to a high utilization ratio ofmaterials thereof. Ink-jet printing will be described in this context byway of an example. In a process of fabricating the OLED displaysubstrate, the heights of the long-side sections 2 of the pixeldefinition layer 8 are set to be greater than the heights of theshort-side sections 3, and after ink-jet printing is finished (that is,an organic light-emitting layer is formed in the opening areas of thepixel definition layer 8 through ink-jet printing), the solvent in theink is removed through vacuum air-pumping, drying, etc., and while thesolute in the ink is being dried into a thin film, an air flow in thedirection of the long sides 6 of the pixels 7 can flow away quickly, andan air flow in the direction of the short sides 5 of the pixels 7 canflow away slowly, thus cancelling out in effect an influence of amicro-acting force and a moving distance of the ink being dried, andenabling the solvent to be redistributed uniformly in the pixel openingareas, so that a film with a uniform thickness can be formed in thepixel opening areas to thereby improve the display effect of the displaydevice, and prolong the service lifetime of the display device.

Further referring to FIG. 1, in an optional embodiment of thisdisclosure, the lengths l1 of the long sides 6, the lengths l2 of theshort sides 5, the heights h1 of the long-side sections 2, and theheights h2 of the short-side sections 3 satisfy h1/h2=(⅓˜¾)a/b, wherethe heights h1 of the long-side sections 2 can range from 1 μm to 5μm,and the heights h2 of the short-side sections 3 can range from 0.5 μm to2.5 μm. The particular heights of the long-side sections 2 and theshort-side sections 3 of the pixel definition layer 8 will not belimited, and the particular proportional relationship between heights ofthe long-side sections 2, and the heights of the short-side sections 3of the pixel definition layer 8, and the lengths of the long sides 6,and the lengths of the short sides 5 of the pixel opening areas will notbe limited, and an appropriate proportional relationship can be selectedto thereby balance an influence of a micro-acting force and a movingdistance of the ink being dried, so as to form a film with a uniformthickness in the pixel opening areas.

As illustrated in FIG. 1 to FIG. 4, in an optional embodiment of thisdisclosure, the wall side of the pixel definition layer 8 facing thepixels is a slope face 4, and the particular angle of the slope face 4facing the pixels will not be limited; and optionally, when the slopeangle of the slope face 4 of the pixel definition layer 8 facing thelong sides 6 of the pixels 7 is equal to the slope angle of the slope 4thereof facing the short sides 5 of the pixels, an influence upon thethickness of a film to be formed while the ink is being dried, due todifferent angles of the slopes of the long-side sections 2 and theshort-side sections 3 can be alleviated in effect while the film isbeing formed in the pixel opening areas.

In an optional embodiment of this disclosure, the pixel definition layer8 can be made of a photosensitive resin organic material, and can bepatterned in a photolithograph process.

In an optional embodiment of this disclosure, the pixel definition layer8 includes a lyophilic material layer, and a lyophobic material layerlocated on the side of the lyophilic material layer away from thesubstrate 1, where the thickness s1 of the lyophobic material layer, andthe thickness s2 of the lyophilic material layer of a long-side sectioncan satisfy s1≥½*s2. The pixel definition layer 8 includes a combinationof the lyophilic material layer and the lyophobic material layer, andthe lyophilic material layer is arranged on the side proximate to thesubstrate 1, so the ink can be prevented in effect from seriouslyclimbing up the edges of the pixels 7 of the substrate 1 during ink-jetprinting to thereby improve the uniformity of the thickness of a filmthroughout the pixels 7.

As illustrated in FIG. 5, an embodiment of this disclosure furtherprovides a display device 9 including the display substrate above.

With this solution, a film with a uniform thickness can be formed in thepixel opening areas of the display substrate to thereby improve thequality of a display panel so as to improve in effect the display effectof the display device, and prolong the service lifetime thereof.

The particular type of the display device will not be limited, and forexample, can be a mobile phone, a tablet computer, an exhibition screen,an on-vehicle computer, etc.

An embodiment of this disclosure further provides a method forfabricating a display substrate, where the method includes the followingsteps:

Forming a pixel definition layer on a substrate, where the pixeldefinition layer includes long-side sections adjacent to long sides ofpixels, and short-side sections adjacent to short sides of the pixels,and the heights of the long-side sections are more than the heights ofthe short-side sections.

As illustrated in FIG. 6, in an optional embodiment of this disclosure,forming the pixel definition layer on the substrate includes:

the step 101 is to form a thin film of the pixel definition layer on thesubstrate;

the step 102 is to form a plurality of opening areas on the thin film ofthe pixel definition layer, where each opening area corresponds to oneof the pixels; and

the step 103 is to thin sections of the thin film of the pixeldefinition layer, which are adjacent to the short sides of the pixels.

As illustrated in FIG. 7, in an optional embodiment of this disclosure,forming the pixel definition layer on the substrate includes:

the step 201 is to form a thin film of the pixel definition layer on thesubstrate;

the step 202 is to thin sections of the thin film of the pixeldefinition layer, which are adjacent to the short sides of the pixels;and

the step 203 is to form a plurality of opening areas on the thin film ofthe pixel definition layer, where each opening area corresponds to oneof the pixels.

Patterns of respective layers on the substrate are typically fabricatedin a patterning process typically including film formation, photo-resistcoating, exposure, development, and etching, photo-resist stripping,etc., where a metal layer is typically formed through physical vapordeposition (e.g., magnetically controllable spraying), and patternedthrough wet etching, and a non-metal layer is typically formed throughchemical vapor deposition, and patterned through dry etching.

It shall be noted that the step 102 and the step 103 can be performed inthe same patterning process, particularly using a half-tone mask, or thestep 102 and the step 103 can be performed in different patterningprocesses; and alike the step 202 and the step 203 can be performed inthe same patterning process, or in different patterning processes.

Optionally, forming the thin film of the pixel definition layer on thesubstrate in the step 101 or the step 201 includes: forming a lyophilicmaterial layer on the substrate; and forming a lyophobic material layeron the side of the lyophilic material layer away from the substrate.

Optionally, the method for fabricating a display substrate according tothe embodiment of this disclosure can further include the step offorming an organic light-emitting layer in the opening areas usingsolution. For example, the organic light-emitting layer in OLED displayelements are formed through ink-jet printing, screen printing, etc., tothereby form the organic light-emitting layer with a uniform thickness.

With the method for fabricating a display substrate according to theembodiment of this disclosure, the heights of the long-side sections ofthe pixel definition layer are set more than the heights of theshort-side sections thereof, and after ink-jet printing is finished, thesolvent in the ink can be removed through vacuum air-pumping, drying,etc., and while the solute in the ink is being dried into a thin film,an air flow in the direction of the long sides of the pixels can flowaway quickly, and an air flow in the direction of the short sides of thepixels can flow away slowly, thus cancelling out in effect an influenceof a micro-acting force and a moving distance of the ink being dried,and enabling the solvent to be redistributed uniformly in the pixelopening areas, so that a film with a uniform thickness can be formed inthe pixel opening areas to thereby improve the display effect of thedisplay device, and prolong the service lifetime of the display device.

Evidently those skilled in the art can make various modifications andvariations to the disclosure without departing from the spirit and scopeof the disclosure. Thus the disclosure is also intended to encompassthese modifications and variations thereto so long as the modificationsand variations come into the scope of the claims appended to thedisclosure and their equivalents.

The invention claimed is:
 1. A display substrate, comprising: asubstrate, a plurality of pixels, and a pixel definition layer on thesubstrate, wherein: the plurality of pixels comprise long sides andshort sides formed in pixel opening areas defined by the pixeldefinition layer; the pixel definition layer comprises long-sidesections adjacent to the long sides, and short-side sections adjacent tothe short sides, and heights of the long-side sections are greater thanheights of the short-side sections: a length l1 of at least one of thelong sides, a length l2 of at least one of the short sides, a height h1of at least one of the long-side sections, and a height h2 of at leastone of the short-side sections satisfy h1/h2=(⅓˜¾)l1/l2 to form a filmwith a uniform thickness in the pixel opening areas; wall sides of thepixel definition layer facing the plurality of pixels are slope faces,each of the slope faces are at a slope angle to the substrate, and noneof the slope angle is equal to 90°; a slope angle of the slope facesfacing the long sides of the plurality of pixels is equal to a slopeangle of the slope faces facing the short sides of the plurality ofpixels; and the pixel definition layer comprises a lyophilic materiallayer, and a lyophobic material layer on a side of the lyophilicmaterial layer away from the substrate; a thickness s1 of the lyophobicmaterial layer, and a thickness s2 of the lyophilic material layer of along-side section satisfy s1≥½*s2 to improve the uniformity of thethickness of the film in the pixel opening areas.
 2. The displaysubstrate according to claim 1, wherein the height h1 of at least one ofthe long-side sections ranges from 1 μm to 5 μm, and the height h2 of atleast one of the short-side sections ranges from 0.5 μm to 2.5 μm.
 3. Adisplay device, comprising the display substrate according to claim 1.4. The display device according to claim 3, wherein a height h1 of atleast one of the long-side sections ranges from 1 μm to 5 μm, and aheight h2 of at least one of the short-side sections ranges from 0.5 μmto 2.5 μm.